STUDY OF CYTOKINES IN ULCERATIVE-COLITIS

We investigated the lymphocyte-activation antigens and the expression of cytokine genes in the mucosa of ulcerative colitis (UC). Fresh colo nic mucosal biopsy specimens from patients with UC and controls were f ixed for the immunohistochemical study of CD4, HLA-DR, and CD25, and o ther specimens were prepared for the RNA analysis of cytokines. Gene e xpression was evaluated by the reverse transcription-polymerase chain reaction, and the radioactivity of dot-blotted amplified cDNA was stan dardized by co-amplified beta-actin cDNA. The inflamed mucosa of activ e UC showed increased CD4 + DR + and CD25 + cells in comparison with c ontrol subjects. Active UC showed significantly increased mRNA express ion of IL-1 beta, IL-2R alpha, IL-6, IL-8, and TNF alpha compared with the controls. We found no significant difference in the mRNA expressi on for IL-2, IL-4, IL-10, and IFN-gamma between active UC and controls . Increased CD4 + DR + and CD25 + cells in active UC mucosa indicate m ucosal CD4(+) T cell activation in the lamina propria, but we did not clarify Th1 or Th2 specific T cell activation from our study of cytoki ne mRNA expression. The increased mRNA expression for IL-1 beta, IL-6, and TNF alpha in the mucosal lesions of UC indicates that these infla mmatory cytokines may play important roles in the pathogenesis of UC.